The cab of a conventional pickup truck typically has a generally rectangular appearance and a depth sufficient to accommodate the comfortable seating of passengers. In order to maximize the cargo capacity in the pickup truck bed or box, the cab typically terminates in a near vertical wall immediately behind the passenger seats. Many pickup truck designs can be referred to as having an "extended cab." This generally means the cab is extended to provide a space behind the passenger seats. In certain pickup truck designs, the space is large enough to include an additional passenger seating arrangement and a door. The generally rectangular cab structure projecting abruptly into the air stream tends to create a high drag force on the truck as it travels along the road.
Numerous pickup truck cab fairings have been proposed to decrease drag effect and direct air flow over the cab. By decreasing drag effect, cab fairings can also improve vehicle mileage. These devices also can reduce air turbulence within the truck bed and protect cargo carried within. They have the additional advantages of reducing the glare from the sun into the cab for the benefit of the passengers, and shielding cargo within the bed from the sun. Cab fairings also add a decorative look to trucks, extending the cab lines of the truck and making trucks look sportier. Cab fairings provide a surface for mounting of lights, antennas or horns. Cab fairings are seldom included in pickup trucks as they leave the factory, and so they must be retrofitted to existing vehicles.
Exemplary cab fairings are described in U.S. Pat. No. 5,018,779 to Lund, and U.S. Design Patent Nos. 281,487 to Chapman, 286,143 to Lund, 294,242 to O'Neill, and 295,084 to Weber.